A near-infrared plasmonic biosensor for detection of morphine and codeine in biological samples based on the end-to-end assembly of modified gold nanorods.

The analytical determination of opiates in biological samples is a critical mission and remains a challenge for almost all judicial and clinical drug testing panels due to their high abuse potential. Based on the high sensitivity of the longitudinal surface plasmon resonance (LSPR) peak of gold nanorods (AuNRs), we successfully developed a novel and simple refractive index sensing platform for detection of morphine (MOR) and codeine (COD) by means of 2-amino-5-mercapto-1,3,4-thiadiazole functionalized gold nanorods (AMTD-AuNRs) in aqueous solution, which is, to the best of our knowledge, the first report on the assay of MOR and COD using AuNRs. AMTD molecules strongly anchor onto the tips of AuNRs via the mercapto group and subsequent hydrogen-bonding interactions between AMTD and the analytes induced end-to-end chain assembly of AuNRs and a consequent decrease of the LSPR absorption band at 850 nm along with a bathochromic shift and emergence of a new hybridized plasmon mode at 1050 nm which was characterized using a Vis-NIR spectrophotometer. After systematic optimization, the absorbance ratio (A1050/A850) was proportional to the concentration of MOR in the ranges of 0.08-5 µM and 0.2-8 µM for COD without any significant effect from possible interferents. Furthermore, detection limits of 40 and 62 nM were achieved for MOR and COD, respectively, which are much lower than the cut-off level of 2000 ng mL-1 for opiates in urine samples set by the Substance and Abuse Mental Health Services Administration (SAMHSA). Eventually, as proof-of-applicability, human urine and blood serum samples spiked with MOR and COD were analyzed and excellent recoveries ranging from 94.4 to 108.9% were obtained, demonstrating the successful applicability of the designed refractive index probe in real biological specimens.

Urine and hair drug test results associated with daily consumption of codeine-predominant poppy seed food products.

This study examined the urine and hair opiate profiles associated with the daily consumption of presumptive codeine-predominant poppy seed food products. Ten participants consumed one of five food products at breakfast for 10 consecutive days. Baseline urine and hair samples were collected on Day 1. The urine samples were collected 4, 8 and 12 h following poppy seed consumption on Days 1 and 10, and the first morning void urine samples were collected on Days 2-10. A second hair specimen was collected on Day 20 ± 2. Urine drug test results: Three of the food products were associated with opiate-negative urine drug test results at all time points at a 300 ng/mL cut-off. Two of the food products were associated with opiate-positive drug test results at all non-baseline time points at a 300 ng/mL cut-off. Of these, all samples (n = 60) were codeine-positive, and 27 (45%) were morphine-positive. Codeine concentrations exceeded morphine concentrations in every sample and always by multiples. Thirty-nine of the 60 samples (65%) were codeine-positive at a 2,000 ng/mL cut-off, while none of these samples were morphine-positive at this cut-off. None of the 60 samples reached an opiate threshold of 15,000 ng/mL, although one participant produced a maximum codeine concentration of 13,161 ng/mL (13,854 ng/mg creatinine). There was no clear trend toward increasing urinary opiate concentrations over the course of the study. Hair drug test results: The hair samples of two participants produced quantifiable codeine (41 pg/mg and 51 pg/mg), but no sample reached a common reporting threshold of 200 pg/mg for codeine or morphine.

Poppy Seed Consumption May Be Associated with Codeine-Only Urine Drug Test Results.

Consumption of poppy seed-containing food products can result in opiate-positive urine drug test results and may pose challenges in distinguishing poppy seed consumption from opiate administration. In this context, guidance has suggested that codeine concentrations exceeding 300 ng/mL coupled with morphine-to-codeine ratios <2 are indicative of codeine consumption and, therefore, exclude poppy seed consumption as a legitimate explanation for the test result. In recent years, we performed independent medical examinations of three individuals who produced codeine-positive/morphine-negative (300 ng/mL) forensic urine drug test results but denied codeine administration, attributing their test results to the consumption of specific poppy seed-containing food products. In the present study, 11 participants consumed one of the 10 unique poppy seed-containing food products, including the three implicated food products. Six of 33 non-baseline urine samples (18%)-representing three food products-were positive for codeine and negative for morphine at 300 ng/mL cut-offs (and therefore featured morphine-to-codeine ratios <2). This study adds to a small literature indicating that consumption of poppy seed-containing food products cannot reliably be distinguished from codeine administration based on previously published urinary opiate concentrations and ratios. An important caveat is that in none of these cases did maximum urinary codeine concentrations exceed 1,300 µg/g creatinine.

Toxicological detection of pholcodine in blood, urine and hair in three cases of fatal intoxication.

Pholcodine is an opioid antitussive reputed for its low toxicity and absence of addictive effect. We report three cases of pholcodine intoxication with fatal outcome. Large concentrations of pholcodine were quantified by gas chromatography coupled to mass spectrometry (GC/MS) in peripheral postmortem blood (respectively 2890 ng/mL, 979 ng/mL and 12,280 ng/mL). Segmental hair analyses by GC/MS and detected pholcodine in three 1.5-2 cm segments (38-161 ng/mg, 8.54-41.6 ng/mg, and 0.26-2.66 ng/mg, respectively). These findings underline that pholcodine can be involved in fatal poisoning and raise the question of misuse or abuse and of taking account of this drug in opioid overdose prevention policies.

Plant Extract and Herbal Products as Potential Source of Sorbent for Analytical Purpose: An Experimental Study of Morphine and Codeine Determination Using HPLC and LC-MSMS.

Solid-phase microextraction (SPME) is an analytical method for microextraction of analytes, in which the analytes bind to the sorbent on the surface of the SPME fiber. Many types of chemical agents are used as sorbent; however, many of these sorbents cause secondary contamination or are not cost-effective. Here, aqueous extract of Ferula gummosa was evaluated as potential source of sorbent for simultaneous microextraction of morphine and codeine. For this purpose, multiwalled carbon nanotubes were carboxylated with H2SO4/HNO3 (3:1) and then functionalized with aqueous extract of F. gummosa. Functionalization was confirmed by Fourier transform infrared and Raman spectroscopy measurements as well as scanning electron microscopy analysis. Porous polypropylene hollow fibers were filled with the functionalized carbon nanotubes (CNTs) and used for analyte extraction in urine sample at 40°C and pH 6 for 2 min. Reversed-phase high-performance liquid chromatography (RP-HPLC) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis showed that the fiber could preconcentrate 1 ng/mL of morphine and 0.75 ng/mL codeine in urine sample and was successfully used for 30 times with no significant loss in the extraction efficiency. Limit of detection (LOD) and limit of quantification (LOQ) for morphine were 1 and 3.3 ng/mL, respectively. LOD and LOQ for codeine were determined 0.75 and 2.47 ng/mL, respectively. Recovery of the fiber was 80% and 93% for morphine and codeine, respectively. SPME fiber using extract of F. gummosa plant was used for the detection of a small amount of morphine in urine sample. Therefore, plants can be considered as abundant and cheap sources of sorbent for various analytical purposes.

Metabolism, pharmacokinetics and selected pharmacodynamic effects of codeine following a single oral administration to horses.

OBJECTIVE: To describe the pharmacokinetics and selected pharmacodynamic variables of codeine and its metabolites in Thoroughbred horses following a single oral administration. STUDY DESIGN: Prospective experimental study. ANIMALS: A total of 12 Thoroughbred horses, nine geldings and three mares, aged 4-8 years. METHODS: Horses were administered codeine (0.6 mg kg-1) orally and blood was collected before administration and at various times until 120 hours post administration. Plasma and urine samples were collected and analyzed for codeine and its metabolites by liquid chromatography-mass spectrometry, and plasma pharmacokinetics were determined. Heart rate and rhythm, step counts, packed cell volume and total plasma protein were measured before and 4 hours after administration. RESULTS: Codeine was rapidly converted to the metabolites norcodeine, codeine-6-glucuronide (C6G), morphine, morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G). Plasma codeine concentrations were best represented using a two-compartment model. The Cmax, tmax and elimination t½ were 270.7 ± 136.0 ng mL-1, 0.438 ± 0.156 hours and 2.00 ± 0.534 hours, respectively. M3G was the main metabolite detected (Cmax 492.7 ± 35.5 ng mL-1), followed by C6G (Cmax 96.1 ± 33.8 ng mL-1) and M6G (Cmax 22.3 ± 4.96 ng mL-1). Morphine and norcodeine were the least abundant metabolites with Cmax of 3.17 ± 0.95 and 1.42 ± 0.79 ng mL-1, respectively. No significant adverse or excitatory effects were observed. CONCLUSIONS AND CLINICAL RELEVANCE: Following oral administration, codeine is rapidly metabolized to morphine, M3G, M6G, C6G and norcodeine in horses. Plasma concentrations of M6G, a presumed active metabolite of morphine, were comparable to concentrations reported previously following administration of an analgesic dose of morphine to horses. Codeine was well tolerated based on pharmacodynamic variables and behavioral observations.

A Study of Opiate, Opiate Metabolites and Antihistamines in Urine after Consumption of Cold Syrups by LC-MS/MS.

Studying the origin of opiate and/or opiate metabolites in individual urine specimens after consumption of cold syrups is vital for patients, doctors, and law enforcement. A rapid liquid chromatography-tandem mass spectrometry method using "dilute-and-shoot" analysis without the need for extraction, hydrolysis and/or derivatization has been developed and validated. The approach provides linear ranges of 2.5-1000 ng mL-1 for 6-acetylmorphine, codeine, chlorpheniramine, and carbinoxamine, 2.5-800 ng mL-1 for morphine and morphine-3-ß-d-glucuronide, and 2.5-600 ng mL-1 for morphine-6-ß-d-glucuronide and codeine-6-ß-d-glucuronide, with excellent correlation coefficients (R2 > 0.995) and matrix effects (< 5%). Urine samples collected from the ten participants orally administered cold syrups were analyzed. The results concluded that participants consuming codeine-containing cold syrups did not routinely pass urine tests for opiates, and their morphine-codeine concentration ratios (M/C) were not always < 1. In addition, the distribution map of the clinical total concentration of the sum of morphine and codeine against the antihistamines (chlorpheniramine or carbinoxamine) were plotted for discrimination of people who used cold syrups. The 15 real cases have been studied by using M/C rule, cutoff value, and distribution map, further revealing a potential approach to determine opiate metabolite in urine originating from cold syrups.

[Simultaneous determination of four opioids in urine by solid-phase extraction and derivatization coupled with gas chromatography-mass spectrometry].

Police officers currently use the colloidal gold rapid testing method to detect heroin in the urine of drug abusers, but the results are often rendered erroneous due to the presence of antitussive drugs, which contain opioids. The traditional manual liquid-liquid extraction method for urine testing has low efficiency and poor sensitivity, and hence, it fails to meet the requirements of the public security department to crack down on drug abusers. Therefore, to avoid punishment, most rapid-test-positive people make false claims about intaking cough suppressants. It is imperative to establish a highly efficient automatic method for the simultaneous determination of multiple opioids in urine, to rule out the use of heroin. A method based on solid-phase extraction and derivatization coupled with gas chromatography-mass spectrometry (GC-MS) has been developed for the simultaneous detection of morphine, O6-acetylmorphine, codeine, and acetyl codeine in urine. Since these four opioids exists as cations in acidic aqueous solution, the urine samples collected from dead bodies or drug addicts were adjusted to pH 6 by using phosphate buffer, enriched, and purified by MCX-SPE columns. Then, morphine, O6-acetylmorphine, and codeine were derivatized by N-methyl-N-(trimethylsilyl) trifluoroacetamide (MSTFA) for GC-MS testing. The effects of sample loading and elution flow rate, percentage of formic acid in the wash solvent (methanol), percentage of ammonia in the eluent (methanol), volume of the wash solvent, and drying time of the cartridge on the extraction efficiency were investigated in detail. The best results were obtained under the following conditions:sample loading and elution flow rate, 1.0 mL/min; volume fraction of formic acid in the wash solvent, 3%; volume fraction of ammonia in the eluent solvent, 5%; volume of 3% (v/v) formic acid in methanol (eluent), 1 mL; and drying time of the cartridge, 1 min. The GC-MS results showed good linearity in the range of 0.02-0.8 µg/mL with correlation coefficients (r2) ≥ 0.998. The limits of detection (LODs) and limits of quantification (LOQs) were 0.0016-0.0039 µg/mL and 0.0054-0.0128 µg/mL, respectively. The recoveries of the target analytes were between 93.0% and 110.3% at spiked levels of 0.02, 0.1, and 0.2 µg/mL. As opposed to similar reported methods, our method showed high sensitivity and recovery; furthermore, the matrix interference was eliminated, and the chromatographic peaks of the analytes were completely separated from the impurity peaks at the level of 0.2 µg/mL. The automatic solid-phase extraction equipment is convenient to operate and allows one to process samples in batches. The conditions for solid-phase extraction can be precisely controlled, and the detection accuracy is greatly improved. In addition, a large number of sample tests can be performed by a few experimenters. Hence, this method facilitates simple and rapid forensic toxicology testing and drug abuse monitoring on a large scale.

An integrated microfluidic device for solid-phase extraction and spectrophotometric detection of opium alkaloids in urine samples.

A novel lab-on-chip integrated microfluidic device for solid-phase extraction (SPE) and spectrophotometric detection of morphine (MOR), codeine (COD), and papaverine (PAP) was developed. The extracted analytes were analyzed with a miniature UV-Vis spectrophotometer. The SPE adsorptive phase composed of polyurethane/polyaniline (PU/PANI) nanofibers was fabricated by electrospinning and in situ oxidative polymerization techniques. The sorbent was characterized by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The main factors of extraction such as desorption conditions, pH, salt effect, and extraction time were investigated. The partial least square (PLS) regression was applied to improve the quantification of analytes. The linear dynamic ranges (LDRs) for MOR, COD, and PAP were 4-240, 4-210, and 1-150 ng mL-1, respectively. Finally, the proposed method was successfully applied for the determination of MOR, COD, and PAP in human urine samples and the extraction recoveries were obtained in the range of 66.7-85.0% with RSDs < 8.3%.

Profiling of morphine and codeine in urine after the ingestion of curry containing poppy seed as an evidence for opiates defence in Malaysia.

Consumption of curry containing poppy seeds has raised an issue concerning the opiate content in the urine that might exceed the cut-off value (300ng/mL). The main objective of this study was to examine the morphine and codeine contents in the urine of the consumers after partaking poppy seed-enriched curry in. The volunteers were asked to partake: (a) a single meal and their urines were collected within 24h, or (b) Two meals a day for three consecutive days and their urines were collected within 72h. Two different dosages were also tested in this study: (a) low dosage: 1g/100ml curry (containing 138µg of morphine and 66µg of codeine) and (b) high dosage: 5g/100ml curry (containing 690µg of morphine and 330µg of codeine). The subjects were randomised into the groups using the method of stratified randomization with age and gender groups as covariates. A total of 6 subjects was allocated for each group and placebos were used as control. Results showed that all subjects who consumed low dosage of poppy seeds either in single meal or multiple meals experiment were found negative. However, 1 out of 6high dosage subjects was confirmed positive at a period of 3-6h after the consumption of curry in the single meal study. This outlier maybe due to the lack of water consumption after consuming the curry, thus the low volume of urine was collected and the opiate was concentrated in the urine. On the other hand, 5 out of 6high dosage subjects in the multiple meals experiment were found positive. Majority of these subjects were found positive on the second and third day of the experiment after the second curry meal was consumed. The outlier (negative) in this group might be due to the high consumption of water throughout the experiment and the subject's urine volumes and frequency of urine collection were much higher compared to other subjects. From the result of this study, it can be concluded that partaking high dosages of poppy seed in curry could give a positive response (>300ng/ml+uncertainty of measurement) in the urine, and the water consumption after partaking curry has significant influence for the opiate contents in the urine.

Stability studies in biological fluids during post-analysis custody. Opiate compounds derived from heroin consumption.

In Forensic Toxicology, the evidences have to be maintained under custody for, at least, one year. Depending on the conditions and duration of storage, drug concentrations might have changed considerably since the first analysis. The aim of this study is to evaluate in vitro stability of opiate compounds, derived from heroin consumption, 6-acetylmorphine (6-MAM), morphine (MOR) and codeine (COD), in blood and urine, during post-analysis custody. Parameters evaluated were: time of custody, temperature, addition of preservative (blood) and pH (urine). Blood and urine samples were spiked with the three analytes to give a final concentration of 1000 ng/mL. The prepared samples were divided into 2 groups and stored at two temperatures (4 °C and -20 °C). Each one of these groups was subsequently divided in other two groups: with and without preservative (1%NaF) for blood, and pH 4 and 8 in the case of urine. 6-MAM, MOR and COD were analyzed by GCMS after SPE and derivatization with BSTFA. Analyses were performed in triplicate every two weeks for a year. In blood samples 6-MAM is the only compound that degrades. The best storage conditions were at -20 °C with NaF, with 6-MAM recoveries, after one year of custody, of 47.1 ± 1.5%; while in the other conditions 6-MAM disappeared after 215 days (at 4 °C with NaF), 45 days (at -20 °C without NaF) and 15 days (at 4 °C without preservative). COD does not degrade, with recoveries higher than 90%, in all of the conditions. They ranged from 89.7 ± 3.6% in samples maintained at -20 °C without NaF to 95.9 ± 2.0% in those maintained at 4 °C with NaF. MOR recoveries were lower than those of COD. They ranged from 66.9 ± 3.6%, in frozen samples added with NaF, to 78.6 ± 0.5% in refrigerated samples without preservative. In urine samples the three compounds were stable in all the studied conditions, with the exception of 6-MAM in samples at pH 8 and stored at 4 °C. In these conditions, 6-MAM disappeared after 135 days of custody; while recoveries in the other conditions ranged from 93.7 ± 6.4%, at 4 °C and pH 4, to 85.1 ± 2.0% at -20 °C and pH 8. MOR and COD recoveries were similar in the four conditions. In the case of MOR, they ranged from 82.1 ± 1.2% at 4 °C and pH 4 to 89.5 ± 6.0% at -20 °C and pH 8. As far as COD is concerned, recoveries ranged from 111.6 ± 5.8% at 4 °C and pH 8 to 102.6 ± 1.2% at 4 °C and pH 4. In conclusion, the study showed that the most labile opiate compound is 6-MAM. Its stability mainly depends on urine pH or the addition of preservative, in blood samples. The best storage conditions for samples from heroin consumers are in the freezer, at -20 °C. In addition, blood samples must be added with 1%NaF and urine samples must be buffered at pH 4.

Quantitative analysis of desomorphine in blood and urine using solid phase extraction and gas chromatography-mass spectrometry.

Desomorphine, a semi-synthetic opioid, is a component of the street drug Krokodil. Despite continued reports of Krokodil use, confirmation via toxicological testing remains scarce. The lack of confirmed desomorphine reports may be in part due to the limited published analytical methodology capable of detecting desomorphine at forensically relevant concentrations. In an effort to assist with identification efforts, a robust analytical method was developed and validated. Solid phase extraction (SPE) and gas chromatography-mass spectrometry (GC-MS) were used to determine desomorphine in blood and urine using a deuterated analog as the internal standard. Data was acquired using selected ion monitoring (SIM) mode. Extraction efficiencies in blood and urine were 69% and 90%, respectively. The limits of quantitation in blood and urine were 5 ng/mL and 8 ng/mL, ten-fold lower than previously published methods. Intra- and inter-assay CVs were 2-4% (n = 3) and 3-7% (n = 15), respectively. The method was fully validated in accordance with published guidelines for forensic use. Furthermore, it provides a means by which desomorphine can be identified in toxicology specimens at forensically relevant concentrations, without the need for derivatization.

Analysis of Desomorphine in Urine Using Liquid Chromatography-Tandem Mass Spectrometry.

Desomorphine is a primary component of the drug Krokodil. While reports of Krokodil use continue to appear in the literature, analytically confirmed cases remain quite scarce. This might be attributed to trends in geographical use, and limited published analytical methodology to detect its use. A sensitive analytical method to detect desomorphine was developed and validated to assist with identification efforts. Solid phase extraction and liquid chromatography-tandem mass spectrometry were used to quantitatively identify desomorphine in urine. An isotopically labeled analog was used as the internal standard. Assay performance was evaluated in accordance with published guidelines. The extraction efficiency for desomorphine in urine was 90%, and limits of detection and quantitation were 0.5 ng/mL. The calibration range of the assay was 0.5-500 ng/mL. Bias ranged from -1% to 2% (n = 15), and the intra- and inter-assay CVs were 2-3% (n = 3) and 32-6% (n = 15), respectively. Ion suppression was -20% and -10% at low and high concentrations, respectively. Interferences were assessed using common drugs, including 24 opioids and structurally related compounds. Using this approach, the quantitative analysis of desomorphine in urine is described at forensically relevant concentrations.

Evaluation of an on-site test device for the heroin metabolite 6-acetylmorphine in urine.

Detection of heroin use is an important task in clinical drug testing and can be best performed by using 6-acetylmorphine as the target analyte. This study was performed to evaluate an on-site test for 6-acetylmorphine screening in urine with an assigned cut-off limit at 10 ng/mL. The reference method was a forensic accredited liquid chromatography-tandem mass spectrometry method. The study confirmed that negative controls and negative authentic specimen resulted in negative readings. Low cross-reactivity was recorded from other potential interfering opioids. Prepared standards and commercial calibrators demonstrated that the cutoff level of the test was lower than the assigned value and rather 2 ng/mL. A study using authentic specimens from patients on substitution treatment with methadone, morphine, and buprenorphine confirmed that the real cut-off level was 2 ng/mL. Using this value as cutoff limit the sensitivity and specificity of the test was 100%.

Magnetic Dual-template Molecularly Imprinted Polymer Nanoparticles for the Simultaneous Determination of Acetaminophen and Codeine in Urine Samples by Ion Mobility Spectrometry.

Dual-template magnetic molecularly imprinted polymer nanoparticles were synthesized and used for the solid-phase extraction of acetaminophen and codeine before simultaneous determination by corona discharge ion mobility spectrometry. The magnetic molecularly imprinted polymer nanoparticles were prepared using silica-coated magnetic nanoparticles as supporters, acetaminophen and codeine as template molecules, 3-aminopropyltriethoxysilane and phenyltriethoxysilane as functional monomers, and tetraethoxysilane as a cross-linker. The obtained molecularly imprinted polymer was characterized by transmission electron microscopy, x-ray diffraction and Fourier-transform infrared spectroscopy. The adsorption performance of the imprinted polymers was studied by a series of experiments, indicating a satisfactory recognition ability of products for acetaminophen and codeine. The detection limits of 0.05 and 0.12 µg mL-1, and the dynamic range of 0.20 - 2.0 and 0.40 - 3.0 µg mL-1 were achieved for acetaminophen and codeine, respectively. The proposed method was used for simultaneous determinations of acetaminophen and codeine in urine samples, and the corresponding recoveries were calculated in the range of 87 - 94%. These satisfactory results revealed the ability of the method for a routine analysis of acetaminophen and codeine, simultaneously.

Ultra-sensitive electrochemical sensing of acetaminophen and codeine in biological fluids using CuO/CuFe2O4 nanoparticles as a novel electrocatalyst.

Copper ferrite-copper oxide (CuO-CuFe2O4) nanoparticles as a semiconductor composite with p-n junction were synthesized by co-precipitation reaction. Then, a novel CuO-CuFe2O4 carbon paste modified electrode was fabricated which displays an effectual electrocatalytic response to the oxidation of acetaminophen (AC) and codeine (CO). A linear range of 0.01-1.5 µmol L-1 and 0.06-10.0 µmol L-1 with the detection limits of 0.007 µmol L-1 and 0.01 µmol L-1 were achieved for AC and CO, respectively. The practical usage of the proposed sensor revealed reasonable results for quantification of AC and CO in biological fluids.

Metabolites of Heroin in Several Different Post-mortem Matrices.

In some forensic autopsies blood is not available, and other matrices are sampled for toxicological analysis. The aims of the present study were to examine whether heroin metabolites can be detected in different post-mortem matrices, and investigate whether analyses in other matrices can give useful information about concentrations in peripheral blood. Effects of ethanol on the metabolism and distribution of heroin metabolites were also investigated. We included 45 forensic autopsies where morphine was detected in peripheral blood, concomitantly with 6-acetylmorphine (6-AM) detected in any matrix. Samples were collected from peripheral blood, cardiac blood, pericardial fluid, psoas muscle, lateral vastus muscle, vitreous humor and urine. Opioid analysis included 6-AM, morphine, codeine, and morphine glucuronides. The 6-AM was most often detected in urine (n = 39) and vitreous humor (n = 38). The median morphine concentration ratio relative to peripheral blood was 1.3 (range 0-3.6) for cardiac blood, 1.4 (range 0.07-5.3) for pericardial fluid, 1.2 (range 0-19.2) for psoas muscle, 1.1 (range 0-1.7) for lateral vastus muscle and 0.4 (range 0.2-3.2) for vitreous humor. The number of 6-AM positive cases was significantly higher (P = 0.03) in the ethanol positive group (n = 6; 86%) compared to the ethanol negative group (n = 14; 37%) in peripheral blood. The distribution of heroin metabolites to the different matrices was not significantly different between the ethanol positive and the ethanol negative group. This study shows that toxicological analyses of several matrices could be useful in heroin-related deaths. Urine and vitreous humor are superior for detection of 6-AM, while concentrations of morphine could be assessed from peripheral or cardiac blood, pericardial fluid, psoas muscle and lateral vastus muscle.